Rogan Josh (Kashmiri Slow-Braised Lamb Curry with Yogurt)

Cut 800 g lamb into large chunks and set 150 g plain yogurt out briefly before cooking so it is not added straight from the refrigerator. Put 180 g onion in a heavy pot and cook it slowly over medium-low heat. Stir often and lower the heat if the edges darken before the onion softens, continuing until the onion is evenly deep golden. Add 1 tbsp minced garlic and 1 tbsp minced ginger and cook for about 1 minute. Add the lamb and sear until the exterior firms and loses its raw color. Stir in 150 ml tomato puree, 1.5 tsp paprika, and 2 tsp garam masala. Cook over medium-low heat until the mixture thickens and coats the lamb instead of pooling loosely in the pot. Reduce the heat to low and add the yogurt in three portions, stirring each addition until no white streaks remain before adding the next. Keep the sauce at a quiet simmer because hard boiling can split the yogurt. Leave the lid slightly ajar and cook slowly for about 45 minutes, stirring occasionally. Turn off the heat when the lamb is tender and the sauce is thick enough to cling to each piece.